Describe an experiment to demonstrate te rectilinear propagation of light.

Describe with the help of diagrams, the formation of an (i) solar eclipse and (ii)lunar eclipse.

How is an image formed by a plane mirror different from a shadow?

The distance between the pinhole and the screen in a pinhole camera is doubled from $20 \mathrm{cm} \mathrm{to} 40 \mathrm{cm}$. How will the size of the image change?

When will multiple shadows be formed?